And now to a scare in the sky tonight when a passenger tried to open the emergency room mid flight. Passengers stunned at what they were witnessing. That flight then landed in portland, oregon. Here's abc's david kerley tonight. Reporter: During one of the most critical parts of flight, this man allegedly started yanking on the handle of one of the plane's exits. Alaska airlines said they were ten minutes away from landing when the passenger in row 17, made some unusual statements and started fulling on that handle, trying to open the emergency door. Passengers leapt into action. They took him down. They held him down until the flight attendants could get there with restraints. Those passengers continued to help them restrain this individual, who was wanting to get out mid flight. Reporter: They used shoelaces and seat belts to hold down 23-year-old alexander herrer the experts say he would never got the door open in flight. It simply can't be done. Until you're on the ground, there's enough pressure inside holding all those doors closed. Reporter: Apparentlies held down the 220-pound suspect. The question, why did he do that? David, tonight, that's what investigators are trying to figure out.

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